Closed-Form AoI Analysis for Dual-Queue Short-Block Transmission with Block Error

Timely delivery of information plays an important role in time-sensitive applications like factory automation and monitoring. In this paper, we consider a dual-server short-block wireless communication system to ensure fresh information generated at relatively high update rate to be delivered to destination in real time, where the information is generated at a relatively high update rate, encoded into two short-block queues and delivered in two parallel paths in real time. The age of information (AoI) performance is investigated for the dual-queue system in the presence of block delivery errors. This is the first work to consider both multiple queues and block errors in AoI analysis. An expression for average AoI is derived, based on the Markov-chain process to enable low-complexity system design and optimization, and its correctness is verified by simulations. It is shown that the dual-queue system investigated significantly outperforms the single-queue system in terms of average AoI, peak AoI violation probability and throughput at a relatively high status update rate. The impacts of update rate and blocklength on average AoI are also investigated.